Statistics

AVIS INTERRUPTION DE SERVICE / SERVICE INTERRUPTION NOTIFICATION :
Nous devons procéder à une opération d'entretien du serveur Papyrus qui nécessitera une courte interruption de service le mardi 20 mars 2018 à partir de 8h30 HAE. Nous prévoyons un arrêt du service pour une période approximative de une à deux heures. Merci de votre compréhension. / We must perform a Papyrus server maintenance operation that will require a short service interruption on Tuesday, March 20, 2018 starting at 8:30 am EDT. We are expecting approximately one to two hours of down time during the maintenance. Thank you for your understanding.

Tic disorders affect up to 1% of individuals worldwide and are associated with social stigma. A major obstacle to these disorders’ evaluation and treatment is the large heterogeneity of phenotypes, which could explain the important number of conflicting neurobiological data. Certain variables, like tic complexity and tasks’ cognitive demand, could explain these heterogeneous results. We propose that a better understanding of cognitive impairments often seen in tic disorders could be obtained by studying the chronometry of electrocortical activity underlying inhibition, attention, memory and motor processes. Our aim was to evaluate the impact of tic complexity as well as task response demand on tic patients’ electrocortical profiles. Thus, we compared 12 patients exhibiting simple tics to 12 patients showing complex tics, and matched them to 15 healthy control participants. All participants performed two Oddball tasks in which one required a motor response (button press) and the other a non-motor response (counting). During both tasks, electrophysiological components were recorded, serving as indices of processes underlying attention (P200), inhibition (N200) and memory (P300). Our results revealed that for the non-motor task, both groups of tics patients had an enhanced N200, while only those with simple tics showed a reduced P300. For the motor task, both groups of tics patients exhibited a decreased P300. According to our results, both tic complexity and motor demand can affect neural mechanisms of the processing stream. Conflicting results found in previous studies might have been confounded by tic complexity as well as task motor requirements.